Scarlets coach Wayne Pivac has slammed the decision by organisers of the Guinness PRO14 to fix both games between his champions and their Conference B rivals Leinster during the Six Nations window.

Both bulk suppliers to their respective national teams, who meet in Dublin next weekend, the Welsh region and Irish province were severely diminished at the RDS on Saturday, with 23 front-liners missing due to international involvement alone.

There is plenty of road to run between now and the end of the season, but these two teams -who met in last year's semi-final - could face each other again in the knockout stages of the European Champions Cup and the PRO14 and, if they did, they would field very different teams.

And Pivac believes that the scheduling of these two conference deciders in spring, with the next clash on March 3, is a missed opportunity.

"Personally, I'm just a little bit disappointed that we played Leinster twice in this window last year and then we're playing them twice in this window this year," he said.

"I would have thought that two of the teams from last year who probably played some of the most attractive rugby and scored some of the best tries and were there at the end of the season, don't get to play at full-strength.

"Hopefully we'll get the opportunity to do that at some stage in the season. It's probably a bit disappointing, but we don't control that. I don't think it's very clever."

Clever or not, both teams made the best of it and the Welsh region were satisfied to leave Dublin with a losing bonus point of their own having limited the conference leaders to three tries.

When Luke McGrath crossed for the third within a minute of the restart that looked unlikely, but a scrappy second-half allowed the visitors to stay in the fight and ultimately their increasingly dominant scrum earned them a good result in the circumstances.

The game came at a cost to two squads already decimated by the Six Nations, with Leinster losing McGrath and Rory O'Loughlin and Scarlets pair Johnny McPhillips and Tom Williams exiting early.

Despite the disruption, both sides served up an entertaining first-half, but the standard dropped as the afternoon wore on.

Two tries from the brilliant James Lowe helped establish Leinster's 10-7 half-time lead after McPhillips' early effort.

McGrath's score - created by Jordan Larmour (below) and Lowe -put the home side on course for a significant win, but Dan Jones' last-gasp penalty delivered a potentially priceless bonus point for the Welsh, who take on Ulster next weekend before welcoming Leinster to Parc y Scarlets.

"I don't know how the scheduling works, so that's a question for someone else," Cullen said of the fixtures issue.

"It would be pretty arrogant of me to say that we are the two best teams at the start of the season, so who is to decide that? Talk to the person who does the schedule.

"It was scrappy enough when we played the semi-final, from our point of view, as well - in terms of we were very scrappy. So I don't think a huge amount changed, apart from the result, in that we won the game this time.

"They're a very good team and we will play them again in two weeks' time.

"Both teams have the challenge now of juggling who they have available for these two games.

"There are a lot of factors beyond our control. We knew going into the semi-final that they were a very good team. Did everyone believe it? I don't know.

"And I'm not sure people believed it even after the semi. I think people probably thought Leinster were poor.

"But people knew it after the final, given what they did against a Munster team that had been going very well. The scoreline in that game was fairly emphatic. They are a bloody good team."

Cullen has had to delve deep into his squad during this window as a combination of call-ups and injuries have put a strain on resources.

"It is up to 51 the number (of players used this season) we are at," he said.

"There is huge investment made in those guys and you hope they are ready and they have positive experiences because there is a lot of players missing.

"Don't get me wrong, it is a win and it keeps us, just about, on top of the table."